Problem: $ { {-3} \times \left[\begin{array}{rrr}{-1} & {3} & {2} \\ {4} & {0} & {2}\end{array}\right] = {?} } $
Answer: To multiply a matrix by a number, multiply each item of the matrix by the number. ${\left[\begin{array}{rrr}{-3}\times{-1} & {-3}\times{3} & {-3}\times{2} \\ {-3}\times{4} & {-3}\times{0} & {-3}\times{2}\end{array}\right]}$ Now, simplify: ${\left[\begin{array}{rrr}{3} & {-9} & {-6} \\ {-12} & {0} & {-6}\end{array}\right]}$